Internally dampened percussion rock drill
OwnerWilliam N. Patterson, Glenn R. Pattersoninventors
Life of this patent
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Abstract
A percussion drill, and methods of using the same, including a shank in mechanical alignment with a piston-hammer and a valve in fluid communication with the piston-hammer. The percussion drill further includes an internal hydraulic dampening system for reducing the velocity of the piston-hammer when the shank is forward of a power position relative to the velocity of the piston-hammer when the shank is in a power position. Preferably, the internal hydraulic dampening system includes mechanical alignment of a portion of the piston-hammer with a port in fluid communication with the valve, operable to reduce fluid flow into an area surrounding the valve when the piston-hammer is forward of its position relative to its normal operation.
Claims15
A percussion drill comprising:
- a shank movable between a rower position and a position forward of the power position;
- a valve in fluid communication in with a piston-hammer, wherein the piston-hammer includes a trio section having a forward shoulder, a center area and a back shoulder, the center area having a smaller diameter than the diameter of the forward and back shoulders forming a high pressure fluid communication path from a third port to a second port;
- and
- an internal hydraulic dampening system comprising the back shoulder movable at least partially over the second port and configured to decrease the high pressure fluid flow from the third port into the second port for reducing the fluid flow to the valve in response to the shank being forward of the power position relative to the fluid flow to the valve when the shank is in the power position to thereby slow movement of the valve when the piston-hammer travels forward the power position and thereby reduce the frequency of impact blows when the shank is forward of the rower position.
A percussion drill comprising:
- a shank aligned with a piston-hammer, the shank movable between a power position and a position forward of the power position, wherein the piston hammer and shank are disposed within a first housing having a first port, a second port, a third port and a fourth port and the piston-hammer comprises a front landing, a rear landing and a trip section, the trip section having a center area disposed between a forward shoulder and a back shoulder, the center area having a smaller diameter than the diameter of the forward and back shoulders and disposed within the first housing forming a high pressure fluid path between the third and second ports;
- a valve disposed in a second housing, the second housing having a fifth port, a sixth port and a seventh port to facilitate fluid communication with the piston-hammer;
- and
- an internal hydraulic dampening system comprising the back shoulder movable over the second port and configured to decrease the high pressure fluid flow from the third port to the seventh port in response to the shank being forward the rower position.
Dependencies are inferred from the claim text.